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may be obviated, by adding from a tenth to an eighth part of tallow, which neither gives any bad smell, nor impairs the light; and excellent candles were made with one part of bees wax, and three of the vegetable.
ART. IX. Transactions of the GEOLOGICAL SOCIETY, establish
ed November 1807. Vol. I. London. 1811.
than GEOLOGY. The field of investigation is of such vast extent, the multitude of the facts so immense, and the difficulty of seizing their characteristic features, and describing them with precision so great, that if many hands and many heads are not employed in the work, no progress at all can be expected. Such at least is the case if we are to regard geology as a science founded altogether on experience and observation. It is very true that this has not always been the case; and that it is only of late years that a patient and regular inquiry into facts, has been thought necessary to the formation of a theory of the earth. We are not yet far from the time when the vague and cursory information that every man might glean from the objects that were perpetually before him, when combined and magnified by a powerful imagination, was sufficient for all the purposes of geological speculation. According to this view of the matter, a man might philosophize very well by himself; it was his business not to discover, but to invent; and he stood no more in need of the assistance of others, than if he had been at work in the regions of Poetry or Romance. One might say of these geological theories, as Bacon did of the antient philosophy, quot Theorie receptæ, aut inventæ sunt, tot fabulas
productas et actas censemus, quae Mundos effecerunt fictitios et « scenicos. This was particularly applicable to speculations that went professedly beyond the bounds of nature, and proposed nothing less than to explain the means by which the present constitution of the world has been established. The extravagance of such pretensions could not but lead to visionary and fantastic theories, which men, accustomed to the more sober and cautious exertions of the understanding, were careful to avoid. Geology was considered by them as a species of mental derangement, in which the patient raved continually of comets, deluges, volcanos and earthquakes; or talked of reclaiming the great wastes of the chaos, and converting them into a terraqueous and habitable globe. This unreal mockery, however, though it has endured
long, and continued even to the present day, is now vanishing and melting into air. Geologists appear at length to be coni vinced of two truths, which, though very important, are not, one would think, in themselves very diffieult to be discovered, viz. that before attempting an explanation, it is best to be acquainted with the thing to be explained ; and that it is in mo case the province of science to go beyond the boundaries of nature, and to account for the manner in which the laws which now govern the material world, were at first established.
In this state of things, a vast collection of facts has become necessary to geology; or rather, indeed, geology is nothing else than the general laws and principles which pervade those facts. The diligence and accuracy, therefore, with which they must be observed and described, their prodigious number and variety, and the vast space over which they are scattered, all combine to render geological researches, in a peculiar manner, the objects of social and united exertion, and put it quite out of the power of an individual to proceed far, without the assist ance of others. All the branches of natural philosophy are well known to owe much of their prosperity to the establishment of the academies, and other scientific bodies, which are now so numerous in Europe. There is not, however, any one of all those branches of knowledge, to which the cooperation of num bers is so cssential, as that which has for its object the natural history of the globe itself.
The necessity of collecting facts from all quarters, appear's very clearly from considering, that the geological theories which have hitherto succeeded one another, even when least chimerical, have been founded on facts not universal, nor applicable to the whole earth, but confined only to a small portion of its surface. The theory of Buffon, was the production of a great genius, but very imperfectly informed con.cerning the natural history of the mineral kingdom, and acquainted only with the phenomena of countries where the strata are nearly horizontal. There was 'no provision, accordingly, in his theory, for explaining the vertical strata, or those marks of disturbance that are so prevalent among priinary monntains. Hence it was, that Buffon, possessing a fertility of invention that has been rarely exceeded; a power of combining facts, and bringing them to bear upon one point, by which he continually astonishes, and often convinces 'his reader; and adding to all this, an eloquence that has perhaps never been equalled by any author who did not treat of man, and the affairs of men, -has entirely failed in his theory of the earth. Though he has combined the powers of fire md water in the machinery of his system, he has employed them exactly in the order where they are weakest, giving the first place to fire, and the second to water. Had he been acquainted with the phenomena of mountains, he would certainly have inverted this order, and would have seen that the vertical position of the strata announced the intrusion of some powerful agent, that had disturbed the arrangement of the watery element. Examples of this kind are very numerous. The theory of Lazzaro Moro was nearly cotemporary with that of Buffon, and was formed entirely from those principles which the volcanic countries, and Italy in particular, exhibit in a state of activity. Though it possess great ingenuity, therefore, and have a foundation in facts, it is not of general application. Even the theory of Werner, of all others the most in vogue at the present moment, though laid on foundations broader than any of the former, is in a considerable degree liable to the same censure. The order of the rocks, and the succession of formations, established by the Saxon mineralogist, are suited to the countries which he and his disa ciples have particularly examined ; but, when extended to other parts of the earth's surface, they are continually at fault, and require additions or corrections that combine very ill with the original system. They cannot be applied to the Alps or the Pyrenees; and have been found particularly erroneous when compared with the structure and disposition of the Scottish mountains.
All this tends to show the necessity of setting many hands to work, if we would obtain a just view of the laws which guide, and have guided, the phenomena of the mineral kingdom. For attaining this object nothing is of such consequence as the description of particular countries, and an accurate exposition of the facts which they exhibit. Indeed, if the face of the earth were divided into districts, and accurately described, we have no doubt that, from the comparison of these descriptions, the true theory of the earth would spontaneously emerge without any effort of genius or invention. It would appear as an incontrovertible principle, about which all men, the moment that the facts were stated to them, must of necessity agree; and something would take place like what has happened to the opinions of philosophers concerning the origin of fountains. Înstead of a hundred different theories, about which they disputed with never ending sophistry, there would be a few general maxims, in which all men of sense and information would uniformly acquiesce.
The descriptions, however, that are suited to bring about this revolution, are of a very particular nature, and have not VOL. XIX, NO. 37,
been often exemplified. The degree of precision and of minute detail they require, is difficult to be combined with the general views, without which they can neither be rendered intercsting nor instructive. There are, accordingly, very few naturalists who can be said to have succeeded perfectly in this first and fundamental part of geological inquiry. Saussure is one of those who have done the best ; his account of the face of nature in the grand scenes where his observations were made, is amusing as well as scientific. Dolomieu is another author, whose descriptions have the same charms and the same accuracy. Among living authors, we might mention Von Buch and a few others, who have succeeded in rendering the minuteness and accuracy of detail, consistent with great and comprehensive views, In their descriptions, every particular fact is seen, as connected with some general form, --some extensive pioture, to which it tends to give solidity and relief. They have not been content with barely describing the rocks themselves, which, though the main objects and the foundation of all, are not the only things entitled to attention. The rivers, the mountains, the valleys, the shores, the general face of the country, must all combine to give unity and interest to a geological description.
To all this, we would wish to add the use of a precise and distinct mineralogical language, free from all ambiguity, all ads mixture of theory. Such a language, we regret to say, does not at present exist; and though much has lately been done to im. prove the nomenclature, particularly by the Wernerian School, it is still extremely imperfect, and inferior by many degrees to those of Botany and Chemistry. This throws another difficulty in the way of geological description. We are glad, therefore, to see a Society formed for the purpose of removing or surmounting those difficulties; and to observe that, in its first attempt, so considerable a portion of skill and industry is dis played.
In the account we are to give of the volume before us, we shall confine our remarks to the papers that are strictly geological, and shall pass over, though with much regret, some very interesting memoirs on the analysis or description of different minerals. The bounds within which we must confine our remarks make this restriction necessary, and we shall be glad, on some future occasion, at returning to examine the papers that appear so well entitled to attention,
The paper which begins this volume gives an account of Guernsey and the other islands which stretch across St Michael's Bay, on the coast of Normandy. These islands, we believe, have never been describod by any mineralogist, and form, no doubt, an interesting subject of research. They appear, from Dr MacCulloch's observations, to be chiefly formed of granitic rocks, being parts of a chain which he supposes, with considerable probability, to extend from Cape La Hogue to Ushant, in a line parallel to the granitic chain that runs from Dartmoor, W. S. W: to the Scilly islands. Of the islands in St Michael's Bay, Alderney is the most northerly ; Jersey is nearly south from it, and Guernsey about south-west. In Alderney, the beds of grit, of which there are several in this island, dip towards the north; as the schist of Jersey, lying an its south side, does towards the south. In the island of Sarcq, nearly in the middle between these, but somewhat to the west, the beds are represented as horizontal: In Guernsey, the strata incline to the north. There seems to be, in some of the islands, á considerable variety of rocks, most of them primitive. In Guernsey we find granite, gneiss, syenite, schist, argillaceous porphyrý, &c.; but we are not enabled to determine the po. sitions of these rocks, relatively to one another ; nor the proportions of the island occupied by each. Dr MacCulloch's Sur, vey is imperfect with respect to these particulars, and also as not describing with sufficient precision the peculiar characters of the granite, gneiss, and other rocks which it enumerates: The maps of the islands which he has given, are not calculated to give much information, as they do not express either the courses of the rivers, or the inequalities of ridges of the hills The paper, however, is of value, as treating of countries of which the mineralogy is not at all known. We have understood that Dr MacCulloch is a skilful mineralogist. His Survey appears to have been made several years ago, merely for his own 'amuse ment; and we have no doubt that it is much less perfect than if it had been exécuted at a later period, and with more serious intentions. It is accompanied by several sketches made with great spirit, but which do not contribute nearly so much to the knowledge of the mineralogy of the islands, as maps would have done, in which the different kinds of rock, the rivers, and the chains of hills, had been carefully laid down.
? The next descriptive paper is on the Natural History of the Rock-salt District in the county of Cheshire, by Henry Holland esq., now Dr Holland. This paper seems to us drawn up in the right style of natural history; it unites accurate detail with general views in a remarkable degrees and de scribes phenomena, without any contamination of hypothesis or theory. The salt mines of Cheshire are found near the cente tre of a large plain formed by the southern parts of Lancashire, the northern extremity of Shropshire, and the intervening